Data Types and Expressions

1. 2 Data Types and Expressions C# Programming: From Problem Analysis to Program Design 4th Edition C# Programming: From Problem Analysis to Program Design

2. Compound Operations • Accumulation • Variable on left side of equal symbol is used once the entire expression on right is evaluated Table 2-13 Compound arithmetic operators C# Programming: From Problem Analysis to Program Design

3. Basic Arithmetic Operations (continued) • Order of operations • Order in which the calculations are performed • Example • answer = 100; • answer += 50 * 3 / 25 – 4; • 50 * 3 = 150 • 150 / 25 = 6 • 6 – 4 = 2 • 100 + 2 = 102 C# Programming: From Problem Analysis to Program Design

4. Order of Operations Table 2-14 Operator precedence • Associatively of operators • Left • Right C# Programming: From Problem Analysis to Program Design

5. Order of Operations (continued) Figure 2-13 Order of execution of the operators C# Programming: From Problem Analysis to Program Design

6. Mixed Expressions • Implicit type coercion • Changes int data type into a double • No implicit conversion from double to int • double answer; • answer = 10 / 3; // Does not produce 3.3333333 • int value1 = 440, • anotherNumber = 70; • double value2 = 100.60; • value2 = value1; // ok here – 440.0 stored in value2 C# Programming: From Problem Analysis to Program Design

7. Mixed Expressions • int value1 = 440; • double value2 = 100.60; • value1 = value2; // syntax error as shown in Figure 2-14 Figure 2-14 Syntax error generated for assigning a double to an int C# Programming: From Problem Analysis to Program Design

8. Mixed Expressions (continued) • Explicit type coercion • Cast • (type) expression • examAverage = (exam1 + exam2 + exam3) / (double) count; int value1 = 0, anotherNumber = 75; double value2 = 100.99, anotherDouble = 100; value1 = (int) value2; // value1 = 100 value2 = (double) anotherNumber; // value2 = 75.0 C# Programming: From Problem Analysis to Program Design

9. Formatting Output • You can format data by adding dollar signs, percent symbols, and/or commas to separate digits • You can suppress leading zeros • You can pad a value with special characters • Place characters to the left or right of the significant digits • Use format specifiers C# Programming: From Problem Analysis to Program Design

10. Formatting Output (continued) Table 2-15 Examples using format specifiers C# Programming: From Problem Analysis to Program Design

11. Numeric Format Specifiers Table 2-16 Standard numeric format specifiers C# Programming: From Problem Analysis to Program Design

12. Numeric Format Specifiers(continued) Table 2-16 Standard numeric format specifiers (continued) C# Programming: From Problem Analysis to Program Design

13. Custom Numeric Format Specifiers Table 2-17 Custom numeric format specifiers C# Programming: From Problem Analysis to Program Design

14. Custom Numeric Format Specifiers (continued) Table 2-17 Custom numeric format specifiers (continued) C# Programming: From Problem Analysis to Program Design

15. Width Specifier • Useful when you want to control the alignment of items on multiple lines • Alignment component goes after the index ordinal followed by a comma (before the colon) • If alignment number is less than actual size, it is ignored • If alignment number is greater, pads with white space • Negative alignment component places spaces on right Console.WriteLine("{0,10:F0}{1,8:C}", 9, 14); 9 $14.00 //Right justifies values C# Programming: From Problem Analysis to Program Design

16. Coding Standards • Naming conventions • Identifiers • Spacing conventions • Declaration conventions C# Programming: From Problem Analysis to Program Design

17. Resources Naming Guidelines for .NET – http://msdn.microsoft.com/en-us/library/xzf533w0(VS.71).aspx Writing Readable Code – http://software.ac.uk/resources/guides/writing-readable-source-code#node-131 C# Video tutorials – http://www.programmingvideotutorials.com/csharp/csharp-introductionVisual Studio 2012 – C# – http://msdn.microsoft.com/en-us/library/kx37x362(V=VS.110).aspx C# Programming: From Problem Analysis to Program Design

18. Chapter Summary • Memory representation of data • Bits versus bytes • Number system • Binary number system • Character sets • Unicode C# Programming: From Problem Analysis to Program Design

19. Chapter Summary (continued) • Memory locations for data • Relationship between classes, objects, and types • Predefined data types • Integral data types • Floating-point types • Decimaltype • Boolean variables • Strings C# Programming: From Problem Analysis to Program Design

20. Chapter Summary (continued) • Constants • Assignment statements • Order of operations • Formatting output C# Programming: From Problem Analysis to Program Design